Effects of Dipeptidyl Peptidase-4 Inhibitors on Renal Outcomes in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis

Comparison of renal prognosis between dipeptidyl peptidase-4 inhibitor users and non-users

AIM

To evaluate the renal prognosis of dipeptidyl peptidase-4 inhibitor (DPP-4i) users and non-users using real-world Asian data.

METHODS

Using databases from DeSC Healthcare, Inc., patients aged 30 years or older who used antidiabetic drugs from 2014 to 2021 were identified. Propensity score matching analyses were used to compare renal prognosis between DPP-4i users and non-users. The primary outcomes were estimated glomerular filtration rate (eGFR) decline and end-stage kidney disease (ESKD) development in the eGFR of 45 mL/min/1.73m2 or higher and eGFR of less than 45 mL/min/1.73m2 groups, respectively.

RESULTS

In total, 65 375 and 9866 patients were identified in the eGFR of 45 mL/min/1.73m2 or higher and eGFR of less than 45 mL/min/1.73m2 groups, respectively. In the eGFR of 45 mL/min/1.73m2 or higher group, propensity score matching created 16 002 pairs. A significant difference was observed in the primary outcome of eGFR decline between DPP-4i users and non-users at 2 years (-2.31 vs. -2.56 mL/min/1.73m2: difference, 0.25 mL/min/1.73m2; 95% confidence interval [CI], 0.06-0.44) and 3 years (-2.75 vs. -3.41 mL/min/1.73m2: difference, 0.66 mL/min/1.73m2; 95% CI, 0.39-0.93). In the eGFR less than 45 mL/min/1.73m2 group, propensity score matching created 2086 pairs. After a mean of 2.2 years of observation, ESKD development was 1.15% and 2.30% in users and non-users, respectively, and Kaplan-Meier analysis revealed a significant difference (log rank P = .005).

CONCLUSIONS

This retrospective real-world study revealed that patients using DPP-4is had a better renal prognosis than those not using DPP-4is.

Effect of DPP-4i inhibitors on renal function in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials

AIMS

About 20-40% patients with type 2 diabetes mellitus (T2DM) had an increased risk of developing diabetic nephropathy (DN). Dipeptidyl peptidase-4 inhibitors (DPP-4i) were recommended for treatment of T2DM, while the impact of DPP-4i on renal function remained unclear. This study aimed to explore the effect of DPP-4i on renal parameter of estimated glomerular filtration rate (eGFR) and albumin-to-creatinine ratio (ACR) in T2DM.

METHODS

A systematic search was performed across PubMed, Embase and Cochrane Library. A fixed or random-effects model was used for quantitative synthesis according to the heterogeneity, which was assessed with I2 index. Sensitivity analysis and publication bias were performed with standard methods, respectively.

RESULTS

A total of 17 randomized controlled trials were identified. Administration of DPP-4i produced no significant effect on eGFR (WMD, -0.92 mL/min/1.73m2, 95% CI, -2.04 to 0.19) in diabetic condition. DPP-4i produced a favorable effect on attenuating ACR (WMD, -2.76 mg/g, 95% CI, -5.23 to -0.29) in patients with T2DM. The pooled estimate was stable based on the sensitivity test. No publication bias was observed according to Begg's and Egger's tests.

CONCLUSIONS

Treatment with DPP-4i preserved the renal parameter of eGFR in diabetic condition. Available evidences suggested that administration of DPP-4i produced a favorable effect on attenuating ACR in patients with T2DM. INTERNATIONAL PROSPECTIVE REGISTER FOR SYSTEMATIC REVIEW (PROSPERO) NUMBER: CRD.42020144642.

Ipragliflozin and sitagliptin differentially affect lipid and apolipoprotein profiles in type 2 diabetes: the SUCRE study

BACKGROUND

SGLT2 inhibitors and DPP4 inhibitors have been suggested to affect lipid metabolism. However, there are few randomized controlled trials comparing the effects on the lipid metabolism between the two types of antidiabetic drugs. The SUCRE study (UMIN ID: 000018084) was designed to compare the effects of ipragliflozin and sitagliptin on serum lipid and apolipoprotein profiles and other clinical parameters.

METHODS

This is a multicenter, open-label, randomized, controlled trial. Patients with type 2 diabetes (20-74 years old) with HbA1c levels of 7.0-10.5% and serum triglyceride levels of 120-399 mg/dL (1.35-4.50 mmol/L) on diet and/or oral hypoglycemic agents were enrolled. Subjects were randomized to treatment with ipragliflozin (50 mg/day, n = 77) or sitagliptin (50 mg/day, n = 83). Laboratory measurements were performed at 0, 1, 3, and 6 months of treatment.

RESULTS

Ipragliflozin and sitagliptin reduced fasting plasma glucose, glycoalbumin, and HbA1c almost equally. Ipragliflozin increased HDL-C and decreased apo E. Sitagliptin decreased TG, apo B48, CII, and CIII, but increased LDL-C. The between-treatment differences were significant for HDL-C (P = 0.02) and apo B48 (P = 0.006), and nearly significant for apo A1 (P = 0.06). In addition, ipragliflozin reduced body weight, blood pressure, serum liver enzymes, uric acid, and leptin, and increased serum ketones compared with sitagliptin.

CONCLUSIONS

While ipragliflozin and sitagliptin showed similar effects on glycemic parameters, the effects on serum lipid and apolipoprotein profiles were different. Ipragliflozin may have an anti-atherogenic effect through modulation of HDL-C and apo E compared to sitagliptin through TG and apo B48, CII, and CIII in patients with type 2 diabetes.

Comparative Effects of Glucose-Lowering Medications on Kidney Outcomes in Type 2 Diabetes: The GRADE Randomized Clinical Trial

Importance

Type 2 diabetes (T2D) is the leading cause of kidney disease in the US. It is not known whether glucose-lowering medications differentially affect kidney function.

Objective

To evaluate kidney outcomes in the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness (GRADE) trial comparing 4 classes of glucose-lowering medications added to metformin for glycemic management in individuals with T2D.

Design, Setting, and Participants

A randomized clinical trial was conducted at 36 sites across the US. Participants included adults with T2D for less than 10 years, a hemoglobin A1c level between 6.8% and 8.5%, and estimated glomerular filtration rate (eGFR) greater than or equal to 60 mL/min/1.73 m2 who were receiving metformin treatment. A total of 5047 participants were enrolled between July 8, 2013, and August 11, 2017, and followed up for a mean of 5.0 years (range, 0-7.6 years). Data were analyzed from February 21, 2022, to March 27, 2023.

Interventions

Addition of insulin glargine, glimepiride, liraglutide, or sitagliptin to metformin, with the medication combination continued until the HbA1c was greater than 7.5%; thereafter, insulin was added to maintain glycemic control.

Main Outcomes and Measures

Chronic eGFR slope (change in eGFR between year 1 and trial end) and a composite kidney disease progression outcome (albuminuria, dialysis, transplant, or death due to kidney disease). Secondary outcomes included incident eGFR less than 60 mL/min/1.73 m2, 40% decrease in eGFR to less than 60 mL/min/1.73 m2, doubling of urine albumin-to-creatinine ratio (UACR) to 30 mg/g or greater, and progression of Kidney Disease Improving Global Outcomes stage. Analyses were intention-to-treat.

Results

Of the 5047 participants, 3210 (63.6%) were men. Baseline characteristics were mean (SD) age 57.2 (10.0) years; HbA1c 7.5% (0.5%); diabetes duration, 4.2 (2.7) years; body mass index, 34.3 (6.8); blood pressure 128.3/77.3 (14.7/9.9) mm Hg; eGFR 94.9 (16.8) mL/min/1.73 m2; and median UACR, 6.4 (IQR 3.1-16.9) mg/g; 2933 (58.1%) were treated with renin-angiotensin-aldosterone inhibitors. Mean chronic eGFR slope was -2.03 (95% CI, -2.20 to -1.86) mL/min/1.73 m2 per year for patients receiving sitagliptin; glimepiride, -1.92 (95% CI, -2.08 to -1.75) mL/min/1.73 m2 per year; liraglutide, -2.08 (95% CI, -2.26 to -1.90) mL/min/1.73 m2 per year; and insulin glargine, -2.02 (95% CI, -2.19 to -1.84) mL/min/1.73 m2 per year (P = .61). Mean composite kidney disease progression occurred in 135 (10.6%) patients receiving sitagliptin; glimepiride, 155 (12.4%); liraglutide, 152 (12.0%); and insulin glargine, 150 (11.9%) (P = .56). Most of the composite outcome was attributable to albuminuria progression (98.4%). There were no significant differences by treatment assignment in secondary outcomes. There were no adverse kidney events attributable to medication assignment.

Conclusions and Relevance

In this randomized clinical trial, among people with T2D and predominantly free of kidney disease at baseline, no significant differences in kidney outcomes were observed during 5 years of follow-up when a dipeptidyl peptidase 4 inhibitor, sulfonylurea, glucagonlike peptide 1 receptor agonist, or basal insulin was added to metformin for glycemic control.

Trial Registration

ClinicalTrials.gov Identifier: NCT01794143.

Sodium-glucose cotransporter 2 inhibitors versus dipeptidyl peptidase 4 inhibitors on new-onset overall cancer in Type 2 diabetes mellitus: A population-based study

BACKGROUND

Cancer is currently the second leading cause of death globally. There is much uncertainty regarding the comparative risks of new-onset overall cancer and pre-specified cancer for Type 2 diabetes mellitus (T2DM) patients on sodium-glucose cotransporter 2 inhibitors (SGLT2I) versus DPP4I.

METHODS

This population-based cohort study patients included patients who were diagnosed with T2DM and administered either SGLT2 or DPP4 inhibitors between 1 January 2015 and 31 December 2020 in public hospitals of Hong Kong.

RESULTS

This study included 60,112 T2DM patients (mean baseline age: 62.1 ± 12.4 years, male: 56.36%), of which 18,167 patients were SGLT2I users and 41,945 patients were dipeptidyl peptidase 4 inhibitor (DPP4I) users. Multivariable Cox regression found that SGLT2I use was associated with lower risks of all-cause mortality (HR: 0.92; 95% CI: 0.84-0.99; p= 0.04), cancer-related mortality (HR: 0.58; 95% CI: 0.42-0.80; p ≤ 0.001) and new diagnoses of any cancer (HR: 0.70; 95% CI: 0.59-0.84; p ≤ 0.001). SGLT2I use was associated with a lower risk of new-onset breast cancer (HR: 0.51; 95% CI: 0.32-0.80; p ≤ 0.001), but not of other malignancies. Subgroup analysis on the type of SGLT2I, dapagliflozin (HR: 0.78; 95% CI: 0.64-0.95; p = 0.01) and ertugliflozin (HR: 0.65; 95% CI: 0.43-0.98; p = 0.04) use was associated with lower risks of new cancer diagnosis. Dapagliflozin use was also linked to lower risks of breast cancer (HR: 0.48; 95% CI: 0.27-0.83; p = 0.001).

CONCLUSION

Sodium-glucose cotransporter 2 inhibitor use was associated with lower risks of all-cause mortality, cancer-related mortality and new-onset overall cancer compared to DPP4I use after propensity score matching and multivariable adjustment.

Cardiovascular and Renal Outcomes with SGLT-2 inhibitors and DPP-4 inhibitors Combination Therapy: A Meta-analysis of Randomized Cardiovascular Outcome Trials

OBJECTIVE

The cardiovascular (CV) and renal benefits of SGLT-2 inhibitors (SGLT2i) in people with type 2 diabetes (T2D) are well known. However, similar beneficial effects of SGLT2i in combination with DPP-4 inhibitors (DPP4i) are not known. It is of interest to explore a trial-level meta-analysis to find out this knowledge gap.

METHODS

A literature search was carried out in PubMed and Embase databases until January 31, 2023. All CV outcome trials (CVOTs) reporting the CV and renal outcomes of SGLT2i with or without background DPP4i therapy against the placebo were retrieved. A meta-analysis was subsequently conducted by applying the inverse variance-weighted averages of pooled logarithmic hazard ratio using random effects analysis, primarily.

RESULTS

This meta-analysis showed that the beneficial three-point major adverse cardiovascular events (3P-MACE) composite (three CVOTs; N = 32,418), the composite of CV death or heart failure hospitalization (hHF) (four CVOTs; N = 37,687), hHF (three CVOTs; N = 27,545), CV death (four CVOTs; N = 34,565), and renal outcomes (two CVOTs; N = 25,406) with SGLT2i are similar with or without background DPP4i therapy against the placebo (P_{heterogeneity} = 0.71, 0.07, 0.87, 0.72, and 0.25; respectively). However, against the placebo, the summary estimates for 3P-MACE composite, hHF, and renal outcomes were stronger with SGLT2i alone whilst the summary estimates for CV death or hHF composite were larger with SGLT2i with background DPP4i therapy.

CONCLUSION

Beneficial CV and renal effects of SGLT2i are similar against placebo regardless of background DPP4i therapy.

Sitagliptin Mitigates Diabetic Nephropathy in a Rat Model of Streptozotocin-Induced Type 2 Diabetes: Possible Role of PTP1B/JAK-STAT Pathway

Diabetic nephropathy (DN) is a microvascular complication of diabetes mellitus. This study examined the therapeutic effects of sitagliptin, a dipeptidyl peptidase inhibitor, on DN and explored the underlying mechanism. Male Wistar albino rats (n = 12) were intraperitoneally administered a single dose of streptozotocin (30 mg/kg) to induce diabetes. Streptozotocin-treated and untreated rats (n = 12) were further divided into normal control, normal sitagliptin-treated control, diabetic control, and sitagliptin-treated diabetic groups (n = 6 in each). The normal and diabetic control groups received normal saline, whereas the sitagliptin-treated control and diabetic groups received sitagliptin (100 mg/kg, p.o.). We assessed the serum levels of DN and inflammatory biomarkers. Protein tyrosine phosphatase 1 B (PTP1B), phosphorylated Janus kinase 2 (P-JAK2), and phosphorylated signal transducer activator of transcription (P-STAT3) levels in kidney tissues were assessed using Western blotting, and kidney sections were examined histologically. Sitagliptin reduced DN and inflammatory biomarkers and the expression of PTP1B, p-JAK2, and p-STAT3 (p < 0.001) and improved streptozotocin-induced histological changes in the kidney. These results demonstrate that sitagliptin ameliorates inflammation by inhibiting DPP-4 and consequently modulating the PTP1B-related JAK/STAT axis, leading to the alleviation of DN.

Effects of glucose-lowering agents on cardiovascular and renal outcomes in subjects with type 2 diabetes: An updated meta-analysis of randomized controlled trials with external adjudication of events

AIMS

To investigate the effects of glucose-lowering agents on all-cause mortality, and cardiovascular and renal outcomes in adults with type 2 diabetes.

METHODS

A MEDLINE and EMBASE search was performed to identify randomized controlled trials, published up to 28 February 2022, with a follow-up ≥52 weeks, in which glucose-lowering drugs were compared with either placebo or active comparators. We included only trials reporting formal external adjudication of events. All-cause mortality, 3-point MACE (major cardiovascular events), and hospitalization for heart failure (HHF) were considered as principal outcomes. Doubling of serum creatinine, worsening albuminuria, and renal death were considered as secondary endpoints.

RESULTS

We included randomized controlled trials performed on metformin (n = 17), pioglitazone (n = 20), alpha-glucosidase inhibitors (n = 9), insulin secretagogues (n = 42), dipeptidyl-peptidase-4 inhibitors (n = 67), glucagon-like peptide-1 receptor agonists (n = 45) or sodium-glucose co-transporter-2 inhibitors (SGLT-2i; n = 42) and insulin (n = 18). Glucagon-like peptide-1 receptor agonist and SGLT-2i were associated with a significant reduction in all-cause mortality [Mantel-Haenszel odds ratio (MH-OR), 95% confidence interval: 0.88 (0.83; 0.95) and 0.85 (0.79; 0.91), respectively] and MACE [MH-OR, 95% confidence interval: 0.89 (0.84; 0.94) and 0.90 (0.84; 0.96), respectively]. SGLT-2i was associated with a reduced risk of HHF [MH-OR 0.68 (0.62; 0.75)], worsening albuminuria [MH-OR 0.67 (0.55; 0.80)] and doubling of serum creatinine [MH-OR 0.58 (0.44; 0.79)]. Metformin and pioglitazone were associated with a significantly lower risk of MACE [MH-OR 0.60 (0.47; 0.80) and 0.85 (0.74; 0.97), respectively] and pioglitazone with a higher risk of HHF [MH-OR 1.30 (1.04; 1.62)]. Insulin secretagogues were associated with increased risk of all-cause mortality [MH-OR 1.12 (1.01; 1.24)] and MACE [MH-OR 1.19 (1.02; 1.39)].

CONCLUSIONS

The results of this updated meta-analysis need to be considered in the choice of drug treatment for type 2 diabetes mellitus, which cannot be merely based on the effect of glucose-lowering drugs on long-term glycaemic control.

Treatment of diabetes mellitus has borne much fruit in the prevention of cardiovascular disease

Cardiovascular (CV) disease is the most alarming complication of diabetes mellitus (DM), and a strategy aiming at cardiovascular event prevention in diabetes mellitus has long been debated. Large landmark clinical trials have shown cardiovascular benefits of intensive glycemic control as a 'legacy effect' in newly diagnosed type 2 diabetes mellitus. In contrast, we have learned that excessive intervention aimed at strong glycemic control could cause unexpected cardiovascular death in patients who are resistant to treatments against hyperglycemia. It has also been shown that the comprehensive multifactorial intervention for cardiovascular risk factors that was advocated in the current guideline provided substantial cardiovascular event reduction. The impact of classical antidiabetic agents launched before 1990s on cardiovascular events is controversial. Although there are many clinical or observational studies assessing the impact of those agents on cardiovascular events, the conclusions are inconsistent owing to variable patient backgrounds and concomitant antidiabetic agents among the studies. Moreover, most of them were not large-scale, randomized, cardiovascular outcome trials. In contrast, GLP-1RA (glucagon-like peptide-1 receptor agonist) and SGLT2 (sodium-glucose cotransporter 2) inhibitors have demonstrated undeniable cardiovascular benefits in large-scale, randomized, controlled trials. Whereas GLP-1RAs decrease atherosclerotic disease, especially stroke, SGLT2 inhibitors mainly prevent heart failure. SGLT2 inhibitors are superior to GLP-1RAs with respect to hard renal outcomes. Therefore, it can be said that drugs such as GLP-1RAs and SGLT2 inhibitors that prevent cardiovascular events, in addition to their glucose-lowering effect, are incredible novel tools that we have gained for use in diabetic treatment.

The Effects of Dipeptidyl Peptidase 4 Inhibitors on Renal Function in Patients with Type 2 Diabetes Mellitus

Past studies have confirmed that glucagon-like peptide 1 (GLP-1) receptor agonists can improve renal outcomes in patients with type 2 diabetes mellitus (DM). This study aimed to evaluate whether dipeptidyl peptidase 4 (DPP-4) inhibitors, which elevate GLP-1 levels, also have similar effects on renal function. In this retrospective study, diabetic patients treated with anti-hyperglycemic agents between 2008 and 2011 were selected. We compared the time to first occurrence of estimated glomerular filtration rate (eGFR) decline ≥30% from the baseline between patients treated with DPP-4 inhibitors and those treated with other anti-hyperglycemic drugs. A total of 2202 patients were enrolled. The incidence of eGFR decline ≥30% from the baseline was 10.08% in the DPP-4 inhibitor group and 16.17% in the non-DPP-4 inhibitor group (p < 0.001). The mean time to event was significantly longer in patients receiving DPP-4 inhibitors (2.84 ± 1.60 vs. 1.96 ± 1.30 years, p < 0.001). Patients who were younger than 65 years old, had better baseline eGFR, did not have preexisting hyperlipidemia, or who were untreated with concomitant statin showed greater reductions in the risk of renal function decline (all p for interaction < 0.05). Conclusively, DPP-4 inhibitors used alone or in combination with other glucose-lowering agents were correlated with lower risks of eGFR decline in patients with type 2 DM.

Glomerular filtration rate as a kidney outcome of diabetic kidney disease: a focus on new antidiabetic drugs

Diabetes has reached epidemic proportions, both in Korea and worldwide and is associated with an increased risk of chronic kidney disease and kidney failure (KF). The natural course of kidney function among people with diabetes (especially type 2 diabetes) may be complex in real-world situations. Strong evidence from observational data and clinical trials has demonstrated a consistent association between decreased estimated glomerular filtration rate (eGFR) and subsequent development of hard renal endpoints (such as KF or renal death). The disadvantage of hard renal endpoints is that they require a long follow-up duration. In addition, there are many patients with diabetes whose renal function declines without the appearance of albuminuria, measurement of the eGFR is emphasized. Many studies have used GFR-related parameters, such as its change, decline, or slope, as clinical endpoints for kidney disease progression. In this respect, understanding the trends in GFR changes could be crucial for developing clinical management strategies for the prevention of diabetic complications. This review focuses on the clinical implication of the eGFR-related parameters that have been used so far in diabetic kidney disease. We also discuss the use of recently developed new antidiabetic drugs for kidney protection, with a focus on the GFR as clinical endpoints.

Pharmacoeconomic evaluation of dipeptidyl peptidase-4 inhibitors for the treatment of type 2 diabetes mellitus: a systematic literature review

INTRODUCTION

Dipeptidyl peptidase-4 inhibitors (DPP-4i) are widely used oral antidiabetic agents that exert antihyperglycemic effects in type 2 diabetes mellitus (T2DM) without increased risk of weight gain or hypoglycemic events. The objective of this paper was to systematically review the latest evidence that was associated with the pharmacoeconomic evaluation of DPP-4i for the treatment of patients with T2DM.

AREAS COVERED

We conducted a systematic literature search of eligible articles published since inception up to March 2021 in Web of Science, MEDLINE (via PubMed), and ECONLIT. Fifty-four eligible articles were included in our review, in which DPP-4i were compared to metformin (4 studies), sulphonylurea (SU) (16 studies), alpha-glucosidase inhibitors (AGI) (3 studies), thiazolidinediones (TZD) (4 studies), other DPP-4i (3 studies), sodium-glucose co-transporter-2 inhibitors (SGLT-2i) (10 studies), glucagon-like peptide 1 receptor agonist (GLP-1RA) (18 studies), insulin (5 studies), and other antidiabetic therapies (5 studies).

EXPERT OPINION

This study provided the updated evidence of systematic pharmacoeconomic evaluation associated with DPP-4i for the treatment of patients with T2DM. The evidence from the literature suggested that DPP-4i may be more cost-effective compared to SU and insulin as second-line therapy after metformin but not a cost-effective alternative compared to SGLPT-2i and GLP-1RA.

Comparison of Adverse Kidney Outcomes With Empagliflozin and Linagliptin Use in Patients With Type 2 Diabetic Patients in a Real-World Setting

Background: To compare the effects of empagliflozin and linagliptin use on kidney outcomes of type 2 diabetes mellitus (T2DM) patients in a real-world setting. Methods: The study involved a propensity score-matched cohort comprising new users of empagliflozin or linagliptin with T2DM between January 1, 2013 and December 31, 2018 from a large healthcare delivery system in Taiwan. Clinical outcomes assessed: acute kidney injury (AKI), post-AKI dialysis, and mortality. Cox proportional hazard model was used to estimate the relative risk of empagliflozin or linagliptin use; a linear mixed model was used to compare the average change in estimated glomerular filtration rate (eGFR) over time. Results: Of the 7,042 individuals, 67 of 3,521 (1.9%) in the empagliflozin group and 144 of 3,521 (4.1%) in the linagliptin group developed AKI during the 2 years follow-up. Patients in the empagliflozin group were at a 40% lower risk of developing AKI compared to those in the linagliptin group (adjusted hazard ratio [aHR], 0.60; 95% confidence interval [CI], 0.45-0.82, p = 0.001). Stratified analysis showed that empagliflozin users ≥65 years of age (aHR, 0.70; 95% CI, 0.43-1.13, p = 0.148), or with a baseline eGFR <60 ml/min/1.73 m² (aHR, 0.97; 95% CI, 0.57-1.65, p = 0.899), or with a baseline glycohemoglobin ≦7% (aHR, 1.01; 95% CI, 0.51-2.00, p =0.973) experienced attenuated benefits with respect to AKI risk. A smaller decline in eGFR was observed in empagliflozin users compared to linagliptin users regardless of AKI occurrence (adjusted β = 1.51; 95% CI, 0.30-2.72 ml/min/1.73 m², p = 0.014). Conclusion: Empagliflozin users were at a lower risk of developing AKI and exhibited a smaller eGFR decline than linagliptin users. Thus, empagliflozin may be a safer alternative to linagliptin for T2DM patients.

Effect of Anagliptin versus Sitagliptin on Renal Function: Subanalyzes from the REASON Trial

PURPOSE

The effects of two types of dipeptidyl peptidase-4 (DPP-4) inhibitors on renal function remain unclear. Thus, we investigated the effect of anagliptin (ANA) and sitagliptin (SITA) on renal function in patients with type 2 diabetes who participated in the randomized evaluation of ANA versus SITA on low-density lipoprotein-cholesterol (LDL-C) in diabetes (REASON) trial.

PATIENTS AND METHODS

We measured the estimated glomerular filtration rate (eGFR) and urinary albumin-creatinine ratio (UACR) before and after the REASON trial. ANA 200 mg/day was administered to 177 patients for 52 weeks, while SITA 50 mg/day was given to 176 patients. We investigated the relationship between differences in renal function and differences in hemoglobin A1c (HbA1c) levels, LDL-C levels, and blood pressure (BP).

RESULTS

No significant differences were found in baseline eGFR and UACR between the two groups. The eGFR levels were significantly decreased in both groups; however, the UACR level was unchanged in the ANA group but elevated in the SITA group, although the difference did not reach significance between the two groups. The difference in eGFR was affected by the differences in HbA1c level and BP, and the difference in the UACR was affected by the differences in LDL-C level and BP, which were reduced only in the ANA group.

CONCLUSION

These findings imply that the effects of DPP-4 inhibitors on renal function, especially on UACR, may be different between the types of DPP-4 inhibitors.

Chronic Kidney Disease and SGLT2 Inhibitors: A Review of the Evolving Treatment Landscape

There is currently an unmet need for effective treatment of chronic kidney disease (CKD) that slows disease progression, prevents development of end-stage kidney disease and cardiovascular disease, and prolongs survival of patients with CKD. In the last 20 years, the only agents to show a reduction in the risk of CKD progression in patients with and without type 2 diabetes (T2D) were angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, but neither drug class has provided a decreased risk of all-cause mortality in patients with CKD and evidence for their use in patients with CKD without T2D is relatively limited. This review discusses the mechanisms underlying the progression of CKD, its associated risk factors, and summarizes the potential therapeutic approaches for managing CKD. There is increasing evidence to support the role of sodium-glucose cotransporter 2 (SGLT2) inhibitor therapy in patients with CKD, including data from the designated kidney outcome trials in patients with T2D (CREDENCE) and in patients with or without T2D (DAPA-CKD). These studies showed a significant reduction in the risk of CKD progression with canagliflozin (in patients with T2D) or dapagliflozin (in patients with or without T2D), respectively, with DAPA-CKD being the first trial to show a reduced risk of all-cause mortality. On the basis of these data, individualized treatment with SGLT2 inhibitors represents a promising therapeutic option for patients with diabetic and nondiabetic CKD to slow disease progression.

Management of Hyperglycemia in Older Adults with Type 2 Diabetes

The increasing incidence of type 2 diabetes in the general population as well as enhanced life expectancy has resulted in a rapid rise in the prevalence of diabetes in the older population. Diabetes causes significant morbidity and impairs quality of life. Managing diabetes in older adults is a daunting task due to unique health and psychosocial challenges. Medical management is complicated by polypharmacy, cognitive impairment, urinary incontinence, injurious falls, and persistent pain. Health care providers now have several traditional and contemporary pharmacologic agents to manage diabetes. Avoidance of hypoglycemia is critical; however, evidence-based guidelines are lacking due to the paucity of clinical trials in older adults. For many in this population, maintaining independence is more important than adherence to published guidelines to prevent diabetes complications. The goal of diabetes care in older adults is to enhance the quality of life without subjecting these patients to intrusive and complicated interventions. Recent technological advancements such as continuous glucose monitoring systems can have crucial supplementary benefits in the geriatric population.

Podocyte Glucocorticoid Receptors Are Essential for Glomerular Endothelial Cell Homeostasis in Diabetes Mellitus

Background Proteinuria and glomerular segmental fibrosis are inevitable complications of diabetic nephropathy though their mechanisms are poorly understood. Understanding the clinical characteristics and pathogenesis of proteinuria and glomerular segmental fibrosis in diabetic nephropathy is, therefore, urgently needed for patient management of this severe disease. Methods and Results Diabetes mellitus was induced in podocyte-specific glucocorticoid receptor knockout (GRPKO) mice and control littermates by administration of streptozotocin. Primary podocytes were isolated and subjected to analysis of Wnt signaling and fatty acid metabolism. Conditioned media from primary podocytes was transferred to glomerular endothelial cells. Histologic analysis of kidneys from diabetic GRPKO mice showed worsened fibrosis, increased collagen deposition, and glomerulomegaly indicating severe glomerular fibrosis. Higher expression of transforming growth factor-βR1 and β-catenin and suppressed expression of carnitine palmitoyltransferase 1A in nephrin-positive cells were found in the kidneys of diabetic GRPKO mice. Podocytes isolated from diabetic GRPKO mice demonstrated significantly higher profibrotic gene expression and suppressed fatty acid oxidation compared with controls. Administration of a Wnt inhibitor significantly improved the fibrotic features in GRPKO mice. The glomerular endothelium of diabetic GRPKO mice demonstrated the features of endothelial-to-mesenchymal transition. Moreover, endothelial cells treated with conditioned media from podocytes lacking GR showed increased expression of α-smooth muscle actin, transforming growth factor-βR1 and β-catenin levels. Conclusions These data demonstrate that loss of podocyte GR leads to upregulation of Wnt signaling and disruption in fatty acid metabolism. Podocyte-endothelial cell crosstalk, mediated through GR, is important for glomerular homeostasis, and its disruption likely contributes to diabetic nephropathy.

Coronavirus Disease (COVID)-19 and Diabetic Kidney Disease

The present review describes COVID-19 severity in diabetes and diabetic kidney disease. We discuss the crucial effect of COVID-19-associated cytokine storm and linked injuries and associated severe mesenchymal activation in tubular epithelial cells, endothelial cells, and macrophages that influence neighboring cell homeostasis, resulting in severe proteinuria and organ fibrosis in diabetes. Altered microRNA expression disrupts cellular homeostasis and the renin-angiotensin-system, targets reno-protective signaling proteins, such as angiotensin-converting enzyme 2 (ACE2) and MAS1 receptor (MAS), and facilitates viral entry and replication in kidney cells. COVID-19-associated endotheliopathy that interacts with other cell types, such as neutrophils, platelets, and macrophages, is one factor that accelerates prethrombotic reactions and thrombus formation, resulting in organ failures in diabetes. Apart from targeting vital signaling through ACE2 and MAS, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections are also associated with higher profibrotic dipeptidyl transferase-4 (DPP-4)-mediated mechanisms and suppression of AMP-activated protein kinase (AMPK) activation in kidney cells. Lowered DPP-4 levels and restoration of AMPK levels are organ-protective, suggesting a pathogenic role of DPP-4 and a protective role of AMPK in diabetic COVID-19 patients. In addition to standard care provided to COVID-19 patients, we urgently need novel drug therapies that support the stability and function of both organs and cell types in diabetes.

Diabetes and kidney disease: emphasis on treatment with SGLT-2 inhibitors and GLP-1 receptor agonists

Kidney disease is a frequent microvascular complication of both type 1 and type 2 diabetes. Historic trials have demonstrated that a tight glycaemic control is the most powerful approach to decrease the chances of developing diabetic nephropathy. However, having an HbA1c < 7% does not completely suppress the risk of kidney disease. The observed residual risk is likely ascribable to two phenomena: 1- the presence of risk factors and alterations additive to and independent of glycaemia, and 2- the activation of long-lasting imbalances by periods of exposure to uncontrolled glycemia, a phenomenon referred to as metabolic memory or legacy effect. Long-lasting oxidative stress, epigenetic alterations, cellular senescence, and the resulting chronic low-grade inflammation are all candidate mechanisms explaining the development of nephropathy despite proper control of risk factors. Recently, two classes of drugs, i.e. glucagon-like peptide (GLP) 1 receptor agonists (RA) and sodium-glucose transporter 2 inhibitors (SGLT-i) have changed this scenario. Indeed, cardiovascular outcome and other trials have clearly shown a renoprotective effect for these drugs, well-beyond their glucose-lowering properties. In this review, we summarize: 1- selected key trials and mechanisms underlying the development of diabetic kidney disease and 2- the results relative to renal endpoints in clinical trials of GLP-1 RA and SGLT-2i. Then, we briefly discuss some of the hypotheses posited to explain the marked renoprotective properties of these two classes, evidencing the still existing gaps in knowledge and proposing future directions to further implement the use of these powerful, disease-modifying drugs.

Effects of DPP4 Inhibitors on Renal Outcomes in Diabetes Mellitus: A Systematic Review and Meta-Analysis

OBJECTIVES

This meta-analysis of randomized clinical trials (RCT) intends to evaluate the efficacy of DPP4 Inhibitors (DPP4I) compared with placebo, other antidiabetics (or DPP4I) on renal outcomes, adverse events (AEs), and all-cause mortality.

METHODS

We searched relevant scientific database for RCTs with DPP4I and prespecified renal end point. The effect size (mean difference or risk ratio) was reported with its 95% confidence interval.

RESULTS

Eight RCTs (n = 39040 participants) were included in the analysis. The rate of change in eGFR was not different in DPP4 inhibitor and control group. DPP4I use beyond 52 weeks did not worsen albuminuria progression (RR 0.88; 95% CI 0.80 to 0.96; high quality evidence) compared to placebo. The risk of AEs within 52 weeks (RR 0.93; 95% CI 0.80 to 1.08; moderate quality evidence), beyond 52 weeks (RR 0.98; 95% CI 0.97 to 1.00; low quality evidence), and all-cause mortality (RR 1.04; 95% CI 0.96 to 1.12; very low quality evidence) were similar to placebo. In head-to-head comparison between two DPP4I studies, no significant differences were found between alogliptin and vildagliptin for improvement in eGFR, UACR, or AE at 24 weeks.

CONCLUSIONS

DPP4I do not seem to provide persuasive benefit in the renal outcomes or all-cause mortality in diabetes mellitus, though there was no evidence for increased AEs.

Mineralocorticoid Receptor Antagonists in Diabetic Kidney Disease

Diabetes mellitus is a global health issue and main cause of chronic kidney disease. Both diseases are also linked through high cardiovascular morbidity and mortality. Diabetic kidney disease (DKD) is present in up to 40% of diabetic patients; therefore, prevention and treatment of DKD are of utmost importance. Much research has been dedicated to the optimization of DKD treatment. In the last few years, mineralocorticoid receptor antagonists (MRA) have experienced a renaissance in this field with the development of non-steroidal MRA. Steroidal MRA have known cardiorenal benefits, but their use is limited by side effects, especially hyperkalemia. Non-steroidal MRA still block the damaging effects of mineralocorticoid receptor overactivation (extracellular fluid volume expansion, inflammation, fibrosis), but with fewer side effects (hormonal, hyperkalemia) than steroidal MRA. This review article summarizes the current knowledge and newer research conducted on MRA in DKD.

Comparative Renal Effects of Dipeptidyl Peptidase-4 Inhibitors and Sodium-Glucose Cotransporter 2 Inhibitors on Individual Outcomes in Patients with Type 2 Diabetes: A Systematic Review and Network Meta-Analysis

BACKGROUND

To compare the renal effects of dipeptidyl peptidase-4 (DPP-4) inhibitors and sodium-glucose cotransporter 2 (SGLT2) inhibitors on individual outcomes in patients with type 2 diabetes.

METHODS

We searched electronic databases (MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials) from inception to June 2019 to identity eligible randomized controlled trials of DPP-4 inhibitors or SGLT2 inhibitors that reported at least one kidney outcome in patients with type 2 diabetes. Outcomes of interest were microalbuminuria, macroalbuminuria, worsening nephropathy, and end-stage kidney disease (ESKD). We performed an arm-based network meta-analysis using Bayesian methods and calculated absolute risks and rank probabilities of each treatment for the outcomes.

RESULTS

Seventeen studies with 87,263 patients were included. SGLT2 inhibitors significantly lowered the risks of individual kidney outcomes, including microalbuminuria (odds ratio [OR], 0.64; 95% credible interval [CrI], 0.41 to 0.93), macroalbuminuria (OR, 0.48; 95% CrI, 0.24 to 0.72), worsening nephropathy (OR, 0.65; 95% CrI, 0.44 to 0.91), and ESKD (OR, 0.65; 95% CrI, 0.46 to 0.98) as compared with placebo. However, DPP-4 inhibitors did not lower the risks. SGLT2 inhibitors were considerably associated with higher absolute risk reductions in all kidney outcomes than DPP-4 inhibitors, although the benefits were statistically insignificant. The rank probabilities showed that SGLT2 inhibitors were better treatments for lowering the risk of albuminuria and ESKD than placebo or DPP-4 inhibitors.

CONCLUSION

SGLT2 inhibitors were superior to DPP-4 inhibitors in reducing the risk of albuminuria and ESKD in patients with type 2 diabetes.

Danegaptide Prevents TGFβ1-Induced Damage in Human Proximal Tubule Epithelial Cells of the Kidney

Chronic kidney disease (CKD) is a global health problem associated with a number of comorbidities. Recent evidence implicates increased hemichannel-mediated release of adenosine triphosphate (ATP) in the progression of tubulointerstitial fibrosis, the main underlying pathology of CKD. Here, we evaluate the effect of danegaptide on blocking hemichannel-mediated changes in the expression and function of proteins associated with disease progression in tubular epithelial kidney cells. Primary human proximal tubule epithelial cells (hPTECs) were treated with the beta1 isoform of the pro-fibrotic cytokine transforming growth factor (TGFβ1) ± danegaptide. qRT-PCR and immunoblotting confirmed mRNA and protein expression, whilst a cytokine antibody array assessed the expression/secretion of proinflammatory and profibrotic cytokines. Carboxyfluorescein dye uptake and ATP biosensing measured hemichannel activity and ATP release, whilst transepithelial electrical resistance was used to assess paracellular permeability. Danegaptide negated carboxyfluorescein dye uptake and ATP release and protected against protein changes associated with tubular injury. Blocking Cx43-mediated ATP release was paralleled by partial restoration of the expression of cell cycle inhibitors, adherens and tight junction proteins and decreased paracellular permeability. Furthermore, danegaptide inhibited TGFβ1-induced changes in the expression and secretion of key adipokines, cytokines, chemokines, growth factors and interleukins. The data suggest that as a gap junction modulator and hemichannel blocker, danegaptide has potential in the future treatment of CKD.

SGLT2 Inhibitors and Other Novel Therapeutics in the Management of Diabetic Kidney Disease

Over the past 40 years there has been a steady rise in the number of people with chronic kidney disease due mainly to a significant increase in the number of people with diabetic kidney disease (DKD). Current treatments (blood pressure control, blood sugar control, and renin-angiotensin-aldosterone system inhibitors) have had a significant impact on slowing progression of DKD. But the continued rise illustrates that there is a great need for new medications. Recently, a number of potentially reno-protective medicines have been studied. In this review, these new medications are discussed with respect to both their reported benefits and possible risks.

The effects of dipeptidyl peptidase-4 inhibitors on kidney outcomes

AIMS

To summarize evidence from randomized controlled trials (RCTs) concerning the effects of dipeptidyl peptidase-4 (DPP-4) inhibitors on kidney outcomes in patients with type 2 diabetes mellitus (T2DM).

METHODS

The Medline, EMBASE and Cochrane databases were searched for RCTs comparing DPP-4 inhibitors with a placebo, active comparator or standard care, with at least 500 person-years follow-up in patients with T2DM and with reporting of kidney outcomes. Treatment effects were summarized using random-effects meta-analysis.

RESULTS

Ten trials including 47 955 patients (mean estimated glomerular filtration rate [eGFR] 71 mL/min/1.73m² , mean follow-up 10 762 patient-years per trial) were eligible for inclusion. DPP-4 inhibitors were compared with placebo (five trials), active comparator (three trials), and standard care (two trials). Overall, treatment with DPP-4 inhibitors was associated with a greater decline in eGFR than treatment with the comparators (weighted mean difference -1.12 mL/min/1.73m² , 95% confidence interval [CI] -1.61, -0.62; high-certainty evidence). There were no detectable effects of DPP-4 inhibitors on rates of doubling serum creatinine (risk ratio [RR] 1.10, 95% CI 0.90, 1.34; high-certainty evidence), end-stage kidney disease (RR 0.97, 95% CI 0.77, 1.23; high-certainty evidence), death from kidney causes (RR 1.81, 95% CI 0.67, 4.93; low-certainty evidence), or all-cause mortality (RR 1.01, 95% CI 0.95, 1.09; high-certainty evidence). DPP-4 inhibitors significantly reduced the risks of the surrogate kidney outcome of new albuminuria (RR 0.88, 95% CI 0.8, 0.98; moderate-certainty evidence) and worsening albuminuria (RR 0.88, 95% CI 0.82, 0.94; moderate-certainty evidence). There was no difference in the safety outcome of acute kidney injury (RR 1.04, 95% CI 0.57, 1.87; high-certainty evidence).

CONCLUSIONS

Dipeptidyl peptidase-4 inhibitors are associated with a greater decline in eGFR, despite reducing the development and progression of albuminuria, and have no clear effect on other key kidney outcomes.

Urinary DPP4 correlates with renal dysfunction, and DPP4 inhibition protects against the reduction in megalin and podocin expression in experimental CKD

This study investigated the molecular mechanisms underlying the antiproteinuric effect of DPP4 inhibition in 5/6 renal ablation rats and tested the hypothesis that the urinary activity of DPP4 correlates with chronic kidney disease (CKD) progression. Experiments were conducted in male Wistar rats who underwent 5/6 nephrectomy (Nx) or sham operation followed by 8 wk of treatment with the DPP4 inhibitor (DPP4i) sitagliptin or vehicle. Proteinuria increased progressively in Nx rats throughout the observation period. This increase was remarkably mitigated by sitagliptin. Higher levels of proteinuria in Nx rats compared to control rats were accompanied by higher urinary excretion of retinol-binding protein 4, a marker of tubular proteinuria, as well as higher urinary levels of podocin, a marker of glomerular proteinuria. Retinol-binding protein 4 and podocin were not detected in the urine of Nx + DPP4i rats. Tubular and glomerular proteinuria was associated with the reduced expression of megalin and podocin in the renal cortex of Nx rats. Sitagliptin treatment partially prevented this decrease. Besides, the angiotensin II renal content was significantly reduced in the Nx rats that received sitagliptin compared to vehicle-treated Nx rats. Interestingly, both urinary DPP4 activity and abundance increased progressively in Nx rats. Additionally, urinary DPP4 activity correlated positively with serum creatinine levels, proteinuria, and blood pressure. Collectively, these results suggest that DPP4 inhibition ameliorated both tubular and glomerular proteinuria and prevented the reduction of megalin and podocin expression in CKD rats. Furthermore, these findings suggest that urinary DPP4 activity may serve as a biomarker of renal disease and progression.

Renoprotective Effects of DPP-4 Inhibitors

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD) worldwide. Dipeptidyl peptidase (DPP)-4 inhibitors are widely used in the treatment of patients with type 2 diabetes (T2D). DPP-4 inhibitors reduce glucose levels by inhibiting degradation of incretins. DPP-4 is a ubiquitous protein with exopeptidase activity that exists in cell membrane-bound and soluble forms. It has been shown that an increased renal DPP-4 activity is associated with the development of DKD. A series of clinical and experimental studies showed that DPP-4 inhibitors have beneficial effects on DKD, independent of their glucose-lowering abilities, which are mediated by anti-fibrotic, anti-inflammatory, and anti-oxidative stress properties. In this review article, we highlight the current understanding of the clinical efficacy and the mechanisms underlying renoprotection by DPP-4 inhibitors under diabetic conditions.

Consensus Recommendations by the Asian Pacific Society of Cardiology: Optimising Cardiovascular Outcomes in Patients with Type 2 Diabetes

The Asian Pacific Society of Cardiology convened a consensus statement panel for optimising cardiovascular (CV) outcomes in type 2 diabetes, and reviewed the current literature. Relevant articles were appraised using the Grading of Recommendations, Assessment, Development and Evaluation system, and consensus statements were developed in two meetings and were confirmed through online voting. The consensus statements indicated that lifestyle interventions must be emphasised for patients with prediabetes, and optimal glucose control should be encouraged when possible. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are recommended for patients with chronic kidney disease with adequate renal function, and for patients with heart failure with reduced ejection fraction. In addition to SGLT2i, glucagon-like peptide-1 receptor agonists are recommended for patients at high risk of CV events. A blood pressure target below 140/90 mmHg is generally recommended for patients with type 2 diabetes. Antiplatelet therapy is recommended for secondary prevention in patients with atherosclerotic CV disease.

Loss of Mitochondrial Control Impacts Renal Health

Disruption of mitochondrial biosynthesis or dynamics, or loss of control over mitochondrial regulation leads to a significant alteration in fuel preference and metabolic shifts that potentially affect the health of kidney cells. Mitochondria regulate metabolic networks which affect multiple cellular processes. Indeed, mitochondria have established themselves as therapeutic targets in several diseases. The importance of mitochondria in regulating the pathogenesis of several diseases has been recognized, however, there is limited understanding of mitochondrial biology in the kidney. This review provides an overview of mitochondrial dysfunction in kidney diseases. We describe the importance of mitochondria and mitochondrial sirtuins in the regulation of renal metabolic shifts in diverse cells types, and review this loss of control leads to increased cell-to-cell transdifferentiation processes and myofibroblast-metabolic shifts, which affect the pathophysiology of several kidney diseases. In addition, we examine mitochondrial-targeted therapeutic agents that offer potential leads in combating kidney diseases.

Type 2 diabetes mellitus management in patients with chronic kidney disease: an update

Diabetes mellitus (DM) is a chronic multisystem disease. Diabetic nephropathy (DN) is one of its significant microvascular complications, associated with increased morbidity and mortality. The aim of this article is to review the literature regarding the latest advances in the management of type 2 DM (T2DM) in patients with chronic kidney disease (CKD). We initially refer to the screening guidelines, the diagnostic tests used, the need for novel biomarkers in DN, the recent advances in high-risk patient identification, the recommended glycemic targets, and concerns regarding the accuracy of HbA1c in these patients. Then, a detailed explanation of the appropriate medical management based on evidence from recent trials is presented, analyzed, and discussed. All patients with T2DM should be screened for albuminuria at initial diagnosis and annually thereafter. Proteomics and metabolomics today represent promising diagnostic tools. Optimal glycemic control, with individualized HbA1c targets, is fundamental for reduced onset or delayed progression of DN and microvascular complications, in general. This can be enhanced by lifestyle modifications and pharmacological interventions when needed. Metformin represents the first pharmacological step, with, recently, a broadened indication for patients with impaired renal function. If HbA1c remains above the target in patients with established CKD, SGLT2i or GLP-1 RA are the preferred second-line agents, as introduced in all new guidelines. This change was the result of recent landmark trials that highlighted the superiority of the two aforementioned medication categories in terms of both renal and cardiovascular outcomes.

Renal protection with glucagon-like peptide-1 receptor agonists

There is an unmet need for renoprotective drugs for more pronounced reduction of albuminuria beyond that provided by renin-angiotensin system (RAS) blockers and for effective slowdown of eGFR decline independent of albuminuria. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have proven effective in reducing prespecified secondary composite kidney outcomes in cardiovascular outcome trials. However, GLP-1 RAs showed a prevailing anti-albuminuric effect, additional to that of RAS blockers, and a non-significant risk reduction in worsening of kidney function, at variance with sodium-glucose cotransporter 2 inhibitors. Mechanisms underlying renal protection with GLP-1 RAs are porly understood. Though treatment with GLP-1 RAs resulted in better glycaemic, blood pressure and body weight control versus placebo, correction for on-trial changes in these parameters did not significantly affect results. Anti-inflammatory/anti-oxidant effects via intracellular signalling through protein kinase A, natriuretic effect via inhibition of sodium-hydrogen exchanger 3 and reduction of hyperfiltration have been proposed as direct renoprotective effects.

Novel therapeutic agents for the treatment of diabetic kidney disease

INTRODUCTION

Diabetic kidney disease (DKD) involves multifaceted pathophysiology which increases the risk of cardiorenal events and mortality. Conventional therapy is limited to renin-angiotensin aldosterone system inhibition and management of hyperglycemia and hypertension. Recent clinical trials have demonstrated promising nephroprotective effects of antihyperglycemic agents thus modifying guideline treatment recommendations for type 2 diabetic patients with chronic kidney disease.

AREAS OF COVERED

Relevant studies and clinical trials were searched via PubMed and clinicaltrials.gov through August 2020. Authors offer an update on clinical evidence regarding nephroprotective effects and side effects of sodium-glucose-cotransporter-2 (SGLT2) inhibitors, glucagon-like-peptide-1 (GLP1) agonists and dipeptidylpeptidase-4 (DPP4) inhibitors. They discuss the potential benefits of novel therapy targeting DKD pathogenic processes including inflammation, oxidative stress, fibrosis, and vasoconstriction shown in early phases of clinical trials and offer an opinion on key challenges and directions for future progress.

EXPERT OPINION

SGLT2 inhibitors are the most promising agents for DKD and improving cardiorenal outcomes. Mineralocorticoid-receptor antagonists and janus kinase inhibitors are also promising investigational therapies that target oxidative stress, nitric oxide synthesis, and inflammation. Novel therapeutic targets and the identification of clinically useful biomarkers may provide future therapies that detect early stages of DKD enabling a slower kidney function decline.

Favorable pleiotropic effects of sodium glucose cotransporter 2 inhibitors: head-to-head comparisons with dipeptidyl peptidase-4 inhibitors in type 2 diabetes patients

BACKGROUND

Sodium glucose cotransporter 2 (SGLT2) inhibitors have shown greater reductions of cardiovascular event risks than dipeptidyl peptidase-4 (DPP4) inhibitors, whereby possible mechanisms may involve the better pleiotropic effects of SGLT2 inhibitors. However, no published data are currently available to directly compare glycemic and pleiotropic effects in real-world type 2 diabetes patients initiating SGLT2 inhibitors or DPP4 inhibitors.

METHOD

We conducted a retrospective cohort study by analyzing the Chang Gung Research Database, the largest multi-institutional electronic medical records database in Taiwan. We included patients newly receiving SGLT2 inhibitor or DPP4 inhibitor intensification therapy for type 2 diabetes from 2016 to 2017. We matched SGLT2 inhibitor users to DPP4 inhibitor users (1:4) by propensity scores to ensure comparable characteristics between the groups. We primarily evaluated 1-year post-treatment changes of hemoglobin A1c (HbA1c) after SGLT2 inhibitor or DPP4 inhibitor initiation, using two-tailed independent t-test. We also evaluated post-treatment changes in body weight, systolic blood pressure (SBP), alanine aminotransferase (ALT) and estimated glomerular filtration rate (eGFR) values, associated with SGLT2 inhibitors and DPP4 inhibitors.

RESULTS

We identified a cohort of 2028 SGLT2 inhibitors and 8112 matched DPP4 inhibitors new users. SGLT2 inhibitors and DPP4 inhibitors showed similar HbA1c reductions (- 1.0 vs. - 1.1%; P = 0.076), but patients receiving SGLT2 inhibitors had greater improvements in body weight (- 1.5 vs. - 1.0 kg; P = 0.008), SBP (- 2.5 vs. - 0.7 mmHg; P < 0.001) and ALT values (- 4.1 vs. - 0.0 U/l; P < 0.001) and smaller declines in eGFR values (- 2.0 vs. - 3.5 ml/min/1.73 m2; P < 0.001) when compared to DPP4 inhibitors.

CONCLUSION

SGLT2 inhibitors had glucose-lowering effects comparable to those of DPP4 inhibitors but more favorable pleiotropic effects on body weight, ALT and eGFR changes, potentially improving type 2 diabetes patients' cardio-metabolic disease risks.

Renal Outcomes in Type 2 Diabetes: A Review of Cardiovascular and Renal Outcome Trials

The development of chronic kidney disease (CKD) in people with diabetes is commonplace, and is frequently associated with a significant and unfavourable impact on patient outcomes along with a substantial economic burden. With the development of novel classes of drug therapies in diabetes, there has been a recent focus on cardiovascular safety measures, with dedicated cardiovascular outcome trials (CVOTs) carried out for all new diabetes medications. More recently, there has been a growing regulatory view that such trials should report more specific renal outcomes to ensure simpler comparability between drugs and drug classes. This article explores some of the possible mechanisms by which these drugs may improve renal function in people with diabetes, and it reviews important CVOTs that have reported renal outcomes to date. These include CVOTS of sodium-glucose cotransporter-2 inhibitors (EMPA-REG OUTCOME study, CANVAS study, CREDENCE trial, DECLARE-TIMI trial and DAPA-HF study), dipeptidyl peptidase-4 inhibitors (EXAMINE trial, SAVOR-TIMI 53, TECOS trial and CARMELINA trial) and glucagon-like peptide-1 analogues (ELIXA trial, LEADER trial, SUSTAIN-6 trial, PIONEER-6 trial, EXSCEL trial, HARMONY Outcomes study and the REWIND study). Ongoing cardiovascular and renal outcome studies such as Dapa-CKD, EMPA-KIDNEY, EMPEROR-Preserved and EMPEROR-Reduced are also discussed. The heterogeneity of patient characteristics and reported renal outcomes, which hinders comparisons between trials and drug classes, is highlighted. Novel classes of diabetes therapies present an important opportunity for nephroprotection beyond the blockade of the renin-angiotensin-aldosterone system in this high-risk group. Clinicians should be aware of such benefits when prescribing these medications for people with, and possibly those without, type 2 diabetes.

Effects of Sodium-Glucose Cotransporter 2 Inhibitors on Renal Outcomes in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This study was conducted to investigate the effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on individual renal outcomes in patients with type 2 diabetes. We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials from inception to September 2017 to identify randomized controlled trials comparing SGLT2 inhibitors with placebo or antidiabetic drugs and reporting any renal outcomes in patients with type 2 diabetes. Additionally, we identified 4 articles which were published after the predefined period to include relevant data. A meta-analysis was performed to calculate weighted mean differences (WMDs) and relative risks (RRs) with 95% confidence intervals (CIs) for each renal outcome. We included 48 studies involving 58,165 patients in the analysis. SGLT2 inhibitors significantly lowered urine albumin-to-creatinine ratio (UACR) (WMD, −14.64 mg/g; 95% CI, −25.15 to −4.12; P = 0.006) compared with controls. The UACR-lowering effects of SGLT2 inhibitors were greater with a higher baseline UACR. Overall changes in estimated glomerular filtration rate (eGFR) were comparable between two groups (WMD, 0.19 mL/min/1.73 m²; 95% CI, −0.44 to 0.82; P = 0.552). However, SGLT2 inhibitors significantly slowed eGFR decline in patients with a higher baseline eGFR and a longer duration of treatment. Compared with controls, SGLT2 inhibitors significantly reduced the risk of microalbuminuria (RR, 0.69; 95% CI, 0.49 to 0.97; P = 0.032), macroalbuminuria (RR, 0.49; 95% CI, 0.33 to 0.73; P < 0.001), and worsening nephropathy (RR, 0.73; 95% CI, 0.58 to 0.93; P = 0.012). In addition, the risk of end-stage renal disease was significantly lower in SGLT2 inhibitors than in controls (RR, 0.70; 95% CI, 0.57 to 0.87; P = 0.001). In conclusion, SGLT2 inhibitors had beneficial renal effects by lowering the risk of albuminuria development or progression and reducing the risk of end-stage renal disease compared with placebo or other antidiabetic drugs.